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1.
Bnach 空间中远达和同时远达问题的适定性   总被引:2,自引:0,他引:2  
倪仁兴  李冲 《数学学报》2000,43(3):421-426
本文研究Bn ach空间X中远达和同时远达问题的适定性,在集合的Husdorff距离下,对X中的闭凸子集D和相对弱紧的有界闭子集K,证明了下述结果:若D关于K严格凸和有Kdec性质,则D中所有使远达问题mxx,K是适定的点x全体在D中是Gδ型集.作为应用,得到了同时远达问题适定性的类似结果.  相似文献   

2.
Banach空间中关于有界集的同时远达问题的适定性   总被引:7,自引:1,他引:6  
倪仁兴  李冲 《数学学报》1999,42(5):823-826
本文研究Banach空间中关于有界集的同时远达问题的适定性,在集合的Hausdorff距离下,证明了:对自反局部一致凸Banach空间中的闭有界集K,使所有关于K的同时远达问题是适定的紧凸子集A全体在紧凸子集全体中是Gδ型集.  相似文献   

3.
设C是实Banach空间X中有界闭凸子集且O是C的内点,G是X中非空有界闭的相对弱紧子集.记K(X)为X的非空紧凸子集并赋Hausdorff距离.称广义共同远达点问题maxc(A,G)是适定的是指它有唯一解(x0,z0)且它的每个极大化序列均强收敛到(x0,z0).在C是严格凸和Kadec的假定下,我们运用不同于DeBlasi,MyjalandPapini和Li等人的方法证明了集{A∈K(X);maxc(A,G)是适定的}含有K(X)中稠Gδ集,这本质地推广和延拓了包括DeBlasi,MyjakandPapini和Li等人在内的近期相应结果.  相似文献   

4.
赋范线性空间中同时远达点的唯一性   总被引:1,自引:0,他引:1  
1 引言 设X为一实赋范线性空间,给定X中的子集G和有界子集K,令(?)和C分别表示X的所有非空有界子集与相对紧子集的全体,对A∈B,记 若x_(0)∈K满足sup||a-x_(0)||=Fk(A),则称x_(0)是A关于K的同时远达点,A关于K的同时远达点的全体记为Q_(K)(A),即  相似文献   

5.
该文考察Banach空间上的远达函数的可导性与远达点的存在性间的关系,指出某些Banach空间上的远达函数(对有界闭集而言)具等于1或-1的单侧方向导数蕴含远达点的存在性,并给出了Banach空间CLUR和LUR的新等价刻划.  相似文献   

6.
1 引言 设X是实的Banach空间,S   X是闭子集. 考虑下述多目标优化问题:其中fk,k∈N≡{1,…,n},gi,i∈M≡{1,…,m},hi,j∈P≡{1,…,p}均是定义在某开集(包含S)上的局部Lipschitz函数. 集合S0={x∈S:gi(x)≤0,i∈M,,hi(x)=0,j∈P}称为(VP)的可行解集.(VP)的局部有效解和局部弱有效解的定义见[2].设φ:X→R是局部Lipschitz函数,则 φ(x)称为φ在x处的Clarke广义梯度[3]. 关于非光滑多目标优化问题(V…  相似文献   

7.
一致凸Banach空间中渐近非扩张映象的几乎轨道的渐近行为   总被引:1,自引:0,他引:1  
设X是有Fréchet可微范数的一致凸Banach空间,C是X的有界闭凸子集,T:C→C是一个渐近非扩张映象.证明了,如果{x:n≥1}是T的几乎轨道,则序列{x0}弱几乎收敛到集合∩from∞to(n=1)co{xi:i≥n}∩F(T)的唯一点,其中,F(T)是T的不动点集.  相似文献   

8.
Devil'sStaircaseofK-HWavesinaSeparatingShearLayerwithAcousticExcitationY.F.DONG,Z.L.WEIandC.XUf(Dept.ofMechanicsandEngineerin...  相似文献   

9.
杨富春 《数学杂志》1994,14(2):289-290
Banach空间上凸函数的Gateaux可微点杨富春云南大学本文总设定X是实Banach空间,D是x的非空开凸子集,j:D→R是连续的凸函数。f在x∈D的Gateaux导数,简称G导数。记在x点6可微若则记为f在x∈G(f;D)的G导数}。已经知道,...  相似文献   

10.
A New Class of Banach Spaces with Uniform Normal Structure   总被引:2,自引:0,他引:2  
高继 《东北数学》2001,17(1):103-110
§ 1.Introduction LetXbeanormedlinearspace ,andletS(X) ={x∈X :x =1 }betheunitsphereofX .In 1 94 8,BrodskiiandMilman[1]introducedthefollowinggeometricconcept: Definition 1 ABounded ,convexsubsetKofaBanachspaceXissaidtohavenormalstructureifeveryconvexsubsetHofKthatconta…  相似文献   

11.
LetS be a weakly compact subset of a Banach spaceB. We show that of all points inB which have farthest points inS contains a denseG 5 ofB. Also, we give a necessary and sufficient condition for bounded closed convex sets to be the closed convex hull of their farthest points in reflexive Banach spaces.  相似文献   

12.
首先给出在随机赋范模中子集的随机最远点的概念.进一步,利用随机一致凸性和经典一致凸性之间的联系证明了下面的结果:令(E,||·||)为完备的随机一致凸的随机赋范模,S为E中几乎处处有界并在(ε, λ)一拓扑下的闭子集,则具有S中随机最远点的集合稠于E.  相似文献   

13.
In this paper, we address the question whether in a given Banach space, a Chebyshev center of a nonempty bounded subset can be a farthest point of the set. We obtain a characterization of two-dimensional real strictly convex spaces as those ones where a Chebyshev center cannot contribute to the set of farthest points of a subset. In dimension greater than two, every non-Hilbert smooth space contains a subset whose Chebyshev center is a farthest point. We explore the scenario in uniformly convex Banach spaces and further study the roles played by centerability and Mcompactness in the scheme of things to obtain a step by step characterization of strictly convex Banach spaces.  相似文献   

14.
Farthest points of sets in uniformly convex banach spaces   总被引:4,自引:0,他引:4  
LetS be a closed and bounded set in a uniformly convex Banach spaceX. It is shown that the set of all points inX which have a farthest point inS is dense. Letb(S) denote the set of all farthest points ofS, then a sufficient condition for to hold is thatX have the following property (I): Every closed and bounded convex set is the intersection of a family of closed balls.  相似文献   

15.
We consider the existence and uniqueness of the farthest point of a given set A in a Banach space E from a given point x in the space E. It is assumed that A is a convex, closed, and bounded set in a uniformly convex Banach space E with Fréchet differentiable norm. It is shown that, for any point x sufficiently far from the set A, the point of the set A which is farthest from x exists, is unique, and depends continuously on the point x if and only if the set A in the Minkowski sum with some other set yields a ball. Moreover, the farthest (from x) point of the set A also depends continuously on the set A in the sense of the Hausdorff metric. If the norm ball of the space E is a generating set, these conditions on the set A are equivalent to its strong convexity.  相似文献   

16.
设C是实Banach空间X中有界闭凸子集且0是C的内点,G是X中非空闭的有界相对弱紧子集.记K(X)为X的非空紧凸子集全体并赋Hausdorff距离,KG(X)为集合{A∈K(X);A∩G=}的闭包.称广义共同逼近问题minC(A,G)是适定的是指它有唯一解(x0,z0),且它的每个极小化序列均强收敛到(x0,z0).在C是严格凸和Kadec的假定下,证明了{A∈K(X);minC(A,G)是适定的}含有KG(X)中稠Gδ子集,这本质地推广和延拓了包括De Blasi,Myjak and Papini[1]、Li[2]和De Blasi and Myjak[3]等人在内的近期相应结果.  相似文献   

17.
Farthest points in reflexive locally uniformly rotund Banach spaces   总被引:3,自引:0,他引:3  
IfS is a bounded and closed subset of a Banach spaceB, which is both reflexive and locally uniformly rotund, then, except on a set of first Baire category, the points inB have farthest points inS.  相似文献   

18.
证明了“若K是Banach空间X中的有界闭凸集,0∈intK,则K有弱滴性质当且仅当K0有(WS)性质.”从而证明了文[1]中提出的一个问题.  相似文献   

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